Process for refining of hydrocarbon oil with metallic sodium



Sept. 25, 1945.

Filed Jan. 29, 1944 Patented Sept. 25, 1945 2,385,431 Pnoclzss Fon REFINING oF HYDRocARBoN IL WITH METALLIC Richard S. Vose, Oil Company, of New Jersey Application January 29, 1944, Serial No.

particular oils for the of improving temperature-viscosity of sodium is Swarthmore, Philadelphia, Pa., a corporstion SODIUM Ps., assigner to Sun finely divided form acts as a prornoter or ind uctor, effecting a 3 i i asentar mentioned' diiliculties involved in practicing the tained. 'Within these ranges the frequency isnot process. I have now discovered that the excess critical and any desired number of vibrations per sodium, present in iinely divided form in the resecond may be utilized. A particularly suitable action mixture, may be separated from the mixfrequency is 360 vibrations per second since this ture by magnetic attraction and thereby reeov- 5 may be produced conveniently by means of 60 ered for reuse. Although metallic sediinn gencycle alternating current which has been conerally is considered to be non-magnetic, I have verted to 180 cycle alternating current by means discovered that it is sufficiently susceptible to of a motor generator. As the-oil-sodium mixmagnetic forces to permit efficient recovery in ture flows through the chamber of magnetic osthis manner., Furthermore, I have found that l0 cillator 2t, the vibration of the diaphragm causes colloidal dispersion o! metallic sodium in hydrosubdivision of the sodium thereby forming a carbons may be accomplished in an effective and sodium-in-oil dispersion in which the sodium efficient manner by means oi a magnetic oscillaparticles are of colloidal or quasi-colloidal size. tor operating on a frequency of vibration at least -'The resulting mixture of oil and colloidally diswithin the sonic range and permissibly within persed sodium flows from the center of magnetic the range of supersonics. oscillator'. 2t to booster pump 2| which forces it v' Thus, in the treatment of hydrocarbons with through line 22 to heater 23 and thence to. treatdispersed metallic sodium in amount substaningor soaking tank 24. In heater 23 -the temtially in excess oi :the amount chemically con perature of the mixture is adjusted to a value sumed in the reaction, according to the present Within a range above the melting point of so invention the excess sodium is recovered by means dium but below the cracking temperature of the of a magnetic filter or separator. Also, when it oil, the particular temperature employed in any is required or desired that the treating agent be A given case depending on the charge stock being employed iii-very nely divided form, the dipertreated. In the treatment or lubricating oils a .sion preferentially is effected by means of a 25 temperature of about 40G-450 F. generally is magnetic oscillator er vibrator. These improvepreferable, although higher or lower temperaments permit the treatment to be carried out tures, for example 350525 F., also are suitable. with considerably greater emciency, economsY and In treating tank 24 the mixture is permitted to simplicity than heretofore possible and are parsoak for a time during which ,the desired reacticularly advantageous with regard rto safety astions take place and until the desired degree of pects of handling large--sized quantities oi xnerefining is attained. Treating tank 24 should be tailic sodium. insulated or provided with heating means in The attached ow sheet diagrammatically illusorder to n'iaintain the desired reaction temperatrates a preferred arrangement of apparatus ture. adapted for practicing the invention in a con- The reaction mixture from treating tank 2G tinuous manner. The arrangement, as shown, comprises the refined oil, a solid or substantially has particular reference to the treatment of lusolid sludge or polymer in the form of ne par-s bricating oil although a similar arrangement ticles suspended within the oil, and excess mewould be satisfactory in treating lighter hydrotallic sodium in colloidal form. The mixture is carbons, for example gasolln as long as pro- 40 withdrawn through line 2S by means of pump it visions are made for maintaining sumcient presand is pumped through cooler 21 and lines 28 sure to prevent vaporization of the hydrocarbons and 2t to iiltration apparatus adapted to remove at the temperature of treatment. Each item. of only the sodium, leaving a mixture of oil conappai'atus shown in the ilow sheet, including the taining suspended sludge which is separated in a magnetic oscillator and the magnetic filters, is 46 subsequent filtration step. This apparatus conknown and has been used in the arts and theresists oi one or more magnetic filters or separators `fore need not be illustrated in great detail. illustrated in the drawing as magnetic filters In the drawing l0 designates a storage tapis or ttla and tt-b. A preferred type of magnetic vessel for the eil to be treated and il designates a filter comprises a chamber or casing enclosing a storage tank for metallic sodium which is main- 5o stack of suitably spaced screens made 0i' mastained in molten condition by means otheating netic material and a coil or winding surrounding coil i2. lIhe oil is pumped from storage tank l@ by the chamber and suitably energized from an elecmeans of pump i3 through line l@ to 'heater iii tric power source to eiect magnetization of the wherein it is heated to a temperature above the screens; for example, as illustrated and described meltingpoint of sodiumand thence passes through in U. S. Patent No. 2,074,085 dated March 16, linel to mixer il. Metallic sodium iswithdrawn i937. Another useful type of magnetic filter in from storage tank il by means oi pump it and which a stack of specedvanes is employed in Place passes through line G19 to mixer l'i where .it is of screens is illustrated and described in U. S. mixed with the charge oil. Mixer il is irl- Patent- No.2,331,769. Iter course,istobe undercluded in the arrangement merelyfor the pureo stood that a magnktic inter-comprising a perpose of dlspersing the sodium in the oil in mod= marient magnet to cause magnetization oi. the erately nne form so that the mixture passing. screens or varies instead of an electromagnet also to magnetic oscillator 20 will be relatively unimay be used if desired. Preferentially, two or form. Mixer l1 suitably may take the form of y more magnetic filters are employed and are used a Venturi mixer, although other types of mixc5 alternately in order to permit continuous operaing equipment, for example a centrifugal pump, tion. With the arrangement shown in the acalso may be used. The mixture or oil andan companying drawing, the reaction mixture is dium passes from mixer il to magnetic oscillator caused to new through magnetic lter @it-d, for 2Q. The latterV comprises a steel diaphragm example, by opening valves tl-a and il-d for which is bolted to a steel cover in a manner to 0 a time during which the sodium particles are atiormva chamber therewith and is provided with tracted to and retained by the magnetized screens,

' means (not shown) for vibrating the diaphr alternately with which the mixture is made to electromagnetically. Arrequency of vibration of. ,low through magnetic filter til-b by opening the diaphragm at least within the sonic range valves tl--b and 32--b and closing valves lil-c and permissibly in the supersonic range is maiuand twe for another period of time. During temperature and consequently with less hazard. 45

sludge receiver I2. The reined oil is withdrawn @0 the on-stream period or one of the filters, the proportion of free hydrogen. In treating lubrlother nlter is drained and the retained sodium is eating oils to the degree of refinement usualb de recovered. 'Ihis is accomplished irst by opening aired, roughly 500 cubic feet of hydrogen gas either valve 33`a or 33--b as the case may be (measured under standard conditions) is liberand, while the otr-stream illteris still magnetized. ated per barrel of oil. In the drawing, lines I1. pumping the hydrocarbon mixture out of the lter u and 4l from magnetic oscillator 2l, treatin! by means of pump 34 and passing it through line tank 24 and magnetic nlters lU-a and Jl-b. re-

35 and line 3l containing valve Il to line 2l 5mm/ely, are provided -to collect the hydrogen l coming from treating tank 24 to the on-stream l0 18 considerable, the above-described process may cai-bons in this manner, itis demagnetized. The manufacturing hydrogen. sodium then is withdrawn and pumped by means In practicing the above-described process the Il by closing valve 31 and opening valve 38. 15 excess oi' the amount consumed in the reaction.

units, should be developed within the magnetic effect g, high degree of rennement not les; than the particles on the magnetized surface when the l ligible in comparison to the total amount em of sodium does not vary substantially over a wide The following examples illustrate the eii'ect o1' temperature range, the temperature at which the treating lubricating oilsy in accordance with the filtration is carried out is not critical. A suitable .all present invention. In these examples three distemperature, for example, is 250 F. but lower or --tillate oils derived from naphthenic base crudos dium may be drained from the filter. The cpthe reaction mixture was' attained in the migeration may be carried out at the same temperanetic filtration step. Processing conditions and ture as employed in the treating step and cooler 40 the characteristics of the oil before and after' 1 may be eliminated from the system. 'I'he treatment are shown in the accompanying tabucooler is desirable merely as a safety feature in lation, l

e sodium-free mixture of oil and sludge Approximate tsmgmmremmsgleaves the magnetic illters through line 40 and is neri@ Winston F sent to equipment for separating the sludge from Ffiti'tslgefm mlm" m' the refined oil, shown as continuous rotary filter ,'iuepgnttrigirggirlgs. "Fm". n Although this is a preferred form of apparao Apmodm' mmemreg'g' tus for effecting removal of the sludge, other mi@ mim F.

. r d. i di m deniers. v known types of illtration apparatus may be used. Arpofbxiigepmgerggimm- 7s Also other methods of separation, for example o Ne-free mimfe F bbl. i

...... solvent extraction, distillation or centrifuging. gsrslgnderllnpfsctlcgf.. gioegiigibiem-. may be used in place of filtration il' desired. In 55 Yield femm 0 v01- Pfnt f 9 the preferred method a layer of sludge or polynydggi formed. cu. rc/bbl. of aso (i Ige- 1 Characteristics of the oil passes through cooler 44 wherein it is cooled to suitable storage temperature. Alternatively, the G,v1y'n oil may be cooled to storage temperature prior to Flesh point, c. o. 0.3 r.- the filtration step. From cooler M the renned oil h'f lottclogs l?" F is pumped by means of pump 45 to treated oil vis. s. U. .t 130 r... storage tank 46. h V

In treating oils with colloidal sodium in rela- Pour point, r tively large excess of the amount chemically congemulsiuity im: sumed, the sodium acts as a promoter or inductor Emuis test for reactions in which the charge .stock contgautligll'eb'" stituents having lower hydrogen to carbon ratio lgurfnvtggof-H--- are dehydrogenated and transformed into sludge' gnghcgxiduope or polymer, as stated above. Accordingly, the Conrad@ 4 Approximate temperature in magnetic oscil iator, F 250 tions/second Temperature of treating, F 425-450 'Iime of treating, hours 11 Approximate temperature in magnetic iiltrs, F 250 Force developed in magnetic filters 5Xgravity Approximate temperature of filtration of Nafree mixture, Lbs. of Na used per bbl. of charge "10 Na consumed in reaction Negligible Yield of refined oil, vol. per cent of charge--- '18 Hydrogen formed, cu. ft./bbl. of charge 440 l5 /f/ Characteristics of the oil Gravity, API Flash point, C. 0. C., Fire goint, C. O. C., F Vis. U. at 100F Vis. S. U. at 130F. Vis. S. U. at 210F. Vlscosit index Pour po nt, Color, A. Demulslbllity test Emulsion test Steam emulsion number. Neutralization number Sulfur, per cent Conradson carbon residu Ash content, per cent Sligb oxidation number 55 The tabulated data show that treatment of naphthenic distillate oils in accordance with the present invention changes their temperatureviscoslty relationships to approximate those of paraffin base distillates. By way of comparison, Oil I was solvent extracted by a well known solvent extraction process to yield a product having substantially the same viscosity index as the renned product from Oil I, with the result that a 40 per centl yield of such solvent extracted product was obtained as compared to the 80 per cent yield obtained in the present process. The data also show that the present process causes a marked improvement in oxidation stability of the oil as well as in other characteristics.

I claim:

l. The process of refining liquid hydrocarbon material which comprises subjecting liquid hydrocarbon charge to the action of finely dispersed metallic sodium in amount substantially the amount chemically consumed in the above the melting point of sodium but temperature of the charge, until undesirable constituents of the charge are transformed into a sludge substantially solid at normal temperature, thereby resulting in a reaction mixture comprising refined hydrocarbon material containing sludge and excess sodium in dispersed form, passing said reaction mixture through a separation zone containing a magnetized surface and therein bringing the mixture into contact with said surface and maintaining said surface magnetized sufficiently highly to cause contained sodium particles to be attracted by and retained on said surface, withdrawing the mixture of refined hydrocarbon material and sludge from said separation zone, and then separating refined hydrocarbon material from the sludge.

2. The process defined in claim 1 wherein a magnetic force of intensity not less than five times gravity is magnetically imposed on the sodium particles in said reaction mixture.

3. The process of refining liquid hydrocarbon material which comprises forming a mixture of hydrocarbon charge and metallic sodium in amount substantially in excess of the amount chemically consumed in the reaction, passing said mixture at a temperature above the melting point of sodium but below the cracking temperature of the charge through a magnetic oscillator and therein subjecting the mixture to magnetically induced vibrations of a frequency at least within the sonic range, withdrawing the mixture and passing it to a treating zone, maintaining the mixture within said treating zone at a temperature above the melting point oi sodium but below the cracking temperature of the charge until undesirable constituents of the charge are transformed into a sludge substantially solidv at normal temperature, thereby resulting in a reaction mixture comprising refined hydrocarbon material containing sludge and excess sodium in dispersed form, lpassing said reaction mixture through a separation zone containing a magnetized surface and therein bringing the mixture into contact with said surface and maintaining said surface magnetized sufficiently highly to cause contained sodium particles to be attracted by and retained on said surface, withdrawing the mixture of reiined hydrocarbon material and sludge from said separation zone and then separating the refined hydrocarbon material from the sludge.

4. The process defined in claim 3 wherein a magnetic force of intensity not less than five times gravity is magnetically imposed on the sodium particles in said reaction mixture.

5. The process defined in claim 3 wherein the frequency of vibration of said magnetic oscillator is approximately 360 vibrations per second.

6. The process of improving the viscosity-temperature characteristics and other qualities of mineral lubricating 'oils which comprises subjecting the oil to the action of colloidally dispersed metallic sodium at a temperature above the melting point of sodium but below the cracking temperature of the oil, until undesirable constituents of the oil are dehydrogenated and rendered a sludge substantially solid at normal temperature, utilizing in said procedure an amount of sodium in excess of that required to effect said dehydrogenation and not less than about 16 per cent to 26 per cent by weight of the oil, thereby resulting in a reaction mixture comprising refined oil containing sludge and excess sodium in dispersed foam, passing said reaction mixture through a separation zone containing a magnetized surface and therein bringing the mixture into contact with said surface and maintaining said surface magnetized suiilciently highly to cause contained sodium particles to be attracted by and retained on said surface, withdrawing the mixture of refined oil and sludge from said separation zone and then separating rened oil from the sludge defined in claim 6 wherein a magnetic force of .intensity not less than five times gravity is magnetically imposed on the sodium particles in said reaction mixture.

3. The process of improving viscosity-temperature characteristics and other qualities of mineral lubricating oils which comprises forming a mixture of the oil and not less than about 16 per cent to 26 per cent metallic sodium by weight of the oil, passing said mixture at a temperature above the melting point of the sodium but below the cracking temperature of the oil through a magnetic oscillator and therein subjecting the mixture to magnetically induced vibrations of a formed into a sludge substantially solid at normal to the action of nneiy dispersed metallic sodium temperature, thereby reiulting in a reaction mixl0 in amount substantially ln excess of the amount ture comprising refined cli containing sludge and chemically consumed in the reaction and et a.

g a megnetized surface from which a. mesuntil undesirable constituents of the charge are netic force of intensity not less than ilve times 15 trenstolmed into s sludse substantially solid at tracted by and retained on said surface, with- 20 tact with s. masnetlzed surface from which e renned oil from the sludge.

9. The process denned in claim 8 wherein c sodium particles to be attracted by and reteined temperature within .the range of S50-525 F. is 25 on said surface.

f muntained within said treating zone. Mmmm s. voeu. 

